Browsing by Author "Gupta, M"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Effect of temperature and strain rate on compressive response of extruded magnesium nano-composite
    (National Engg. Reaserch Center for Magnesium Alloys, 2015-10-01) Selvam, B; Marimuthu, P; Narayanasamy, R; Senthilkumar, V; Tun, K.S.; Gupta, M
    The hot deformation behaviour of extruded magnesium-zinc oxide nano composite has been studied using hot compression test. The test was conducted in the temperature range of 250-400 °C and in the strain rate range of 0.01 to 1.5 s-1.The processing map was obtained using the power dissipation efficiency with the functions of temperature and strain rate. The workability and instability domains were observed in the processing map for a nano composite. The optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images were used to confirm the formation of dynamic recrystallization (DRX), dynamic recovery (DRY) and instability regions. The workability region of the composite was identified at a working temperature of 400 °C and the strain rate of 0.01 s-1 from the processing map. The instability regions were observed at higher strain rates (>0.1 s-1) and temperatures (250-400 °C).
  • No Thumbnail Available
    Item
    Experimental and numerical analyses of magnesium alloy hot workability
    (National Engg. Reaserch Center for Magnesium Alloys, 2016-10-25) Abbassi, F; Srinivasan, M; Loganathan, C; Gupta, M
    Due to their hexagonal crystal structure, magnesium alloys have relatively low workability at room temperature. In this study, the hot workability behavior of cast-extruded AZ31B magnesium alloy is studied through hot compression testing, numerical modeling and microstructural analyses. Hot deformation tests are performed at temperatures of 250 °C to 400 °C under strain rates of 0.01 to 1.0 s−1. Transmission electron microscopy is used to reveal the presence of dynamic recrystallization (DRX), dynamic recovery (DRY), cracks and shear bands. To predict plastic instabilities during hot compression tests of AZ31B magnesium alloy, the authors use Johnson–Cook damage model in a 3D finite element simulation. The optimal hot workability of magnesium alloy is found at a temperature (T) of 400 °C and strain rate (ε˙) of 0.01 s−1. Stability is found at a lower strain rate, and instability is found at a higher strain rate.
  • No Thumbnail Available
    Item
    Investigations on the Wear Behaviour and Mechanism of Mg-3Al/5.6Ti Composite under Dry Sliding
    (Polska Akademia Nauk, 2025) Sathish, S; Anandakrishnan, V; Gupta, M
    Magnesium containing 3 weight percentages of aluminium particles and 5.6 weight percentages of titanium particles (reinforcement) was prepared using the disintegrated melt deposition technique to investigate their synergistic effect on the tribological behaviour of Mg-3Al/5.6Ti composite. Metallographic features of the composite samples were analysed using x-ray diffraction analysis and scanning electron microscopy to disseminate the particle distribution and phase formation. The wear behaviour of the samples was studied using dry sliding wear testing by systematically varying load and sliding velocity over a sliding distance of 2000 m. The post-failure analysis was performed on the worn surface of pins, and the collected debris using scanning electron microscopy and the mechanisms involved in the wear behaviour of composite samples were identified.